Water heater



Feb. 13, 1940. F, +i"'wmbHE|M HAL 2,189,749

WATER HEATER 2 Filed July 51, 1937 I 2 Sheets-Sheet 1 Feb. 13, 1940.

F. T. WINDHEIM ET AL WATER HEATER 2 Sheets-Sheet 2 Filed July 31, 1937ENTORS.

N/ TNESS.

Patented Feb. 13, 1940 UNITED STATES WATER HEATER Fred '1'. Windheim andJohn Windheim, Nutley, N. J.

Application July 31, 1937, Serial No. 156,641

Claims.

This invention relates to improvements in domestic water heaters andmore particularly to a tankless, non-storage type water heater forhousehold use in connection with either oil or 5 gas fired burners orboilers.

One of the principal features of the invention resides in combining of adomestic water heater and a boiler booster in a single unit as atankless domestic hot water supply heater, and a water tank container asa heat transfer unit.

Another feature of the invention is the pro vision of a domestic waterheater which embodies the utilizing of the waste heated gases ofcombustion and the heat from the water of a domestic boiler for heatingpurposes without affecting any material temperature change in the boilerwater.

Another feature of the invention is the provision of a domestic waterheater embodying a o down-draft principle of heat control wherein aby-pass from the top of the system to a flue is normally open and whichis automatically closed only when. the heat in the lowest part of thedown draft system reaches a predetermined temperature thus assuringpositive circulation of heated gases through the system and the carryingoff of the gases of combustion from the furnace or boiler.

Another feature of the invention is to provide 20 a tankless domesticwater heater operatively associated with the heat from an oil or gasburner of a domestic furnace which may function for use in the summerseason as well as when the furnace is being used for house heatingpurposes in the winter season, without requiring alterations in thewater heater system. 7

Another feature of the invention consists of a water heating system inwhich water is heated primarily by the heat of the Waste gases of com-40 bustion of a domestic boiler and which includes automatic means forreleasing any excessive accumulation of gases in the system which mightotherwise cause an explosion.

A still further object of the invention is the provision of an efficienteconomical Water heater which may be operatively connected with domesticboilers now in use without radical changes in construction orarrangement of parts.

With these and other objects in view, the in- 0 vention resides in thecertain novel construction,

combination and arrangement of parts, the essential features of whichare hereinafter fully described, are particularly pointed out in theappended claims and are illustrated in the' accom- 55 panying drawings,in which:

shell I! and rising upwardly and leading to a and with which my combinedwater heater and boiler booster unit I l is operatively connected.

The water heater and boiler booster unit ll includes an outer steelcasing or shell l2 which is of substantially oval shape in plan, theinner side of which is lined with suitable insulating material l3. Theshell i2 is supportedupon adjustable legs although any other pedestalsupport maybe provided. The top of the outer casing l2 opens into a gasaccumulator dome ll, the 0 top of which is normally closed by a pair ofoppositely disposed hinged safety blow-ofl doors l5l 5. The dome I4 isconnected at one side by' a horizontally disposed insulated pipe IS withthe flue outlet at the top of the furnace or boiler I0 25 whereby heatedgases of combustion from the furnace will enter the top of the outershell l2 through the dome H. A relatively smaller diameter horizontallydisposed insulated by-pass pipe I! has one of its ends connected to thedome ll opposite the pipe l6, while the other end of the by-pass pipeconnects with a flue pipe I8, the latter being connected adjacent thebottom of the chimney l9. Theby-pass pipe I! has a butterfly damper 20mounted therein from which an actuating rod 2| depends. The lower end ofthe actuating rod extends into a horizontally disposed branch '22 of thefiuepipe l8 and is operatively 40 connected to a temperature responsivedevice in the nature of a spiral thermo coil 23. The butterfiy damper isnormally open but is adapted to automatically close under the action ofthe thermocoil 23 when the temperature in the lower end of the flue pipe[8 reaches a predetermined temperature.

Housed within the outer casing or shell l2 in spaced relation thereto isan inner casing or shell 24 constructed of sheet iron or the like, thesame being supported upon legs 25 which rest upon the bottom of theouter shell l2. The space between the inner and outer sheets constitutesa flue passage for the waste hot gases of combustion from the domesticboiler ID in their passage from the flue pipe I, dome l4 to the lowerend of the flue pipe I 8.

Extending the full height of the inner shell or casing 24 and openingthrough the top and bottom thereof are spaced copper flue tubes 26 thesame being spaced well inwardly of the inner walls of the inner casingor shell 24. Extending the full length of the tubes 26 are spiral flns21 which partition the tubes to provide spiral passages therethrough.Encircling the group of flue tubes 26 and closely spaced relatively tothe outermost tubes 26 of the group is a single spiral copper water coil28, the convolutions of which are closely spaced. The convolutions ofthe water coil 28 are held rigidly spaced by vertical metal clampingplates 29 spaced from the coil by strips oi insulation 30 interposedbetween the plates and the coil. Bolts 3| secure the clamping plates 29together. Due to the arrangement of the flue tubes, the coil 29 issubstantially oval in plan to correspond to the cross sectional contourof the inner and outer casings. It is desired to maintain the coil inspaced relation to the group of flue tubes 28 and strips of insulation32 may be interposed therebetween wherever necessary. The lower end ofthe water coil 23 extends through the inner and outer cas ing's andconnects with a cold water supply pipe 33, whereas the upper end of thecoil extends through the inner and outer casings and connects with a hotwater supply pipe 34. The hot water supply pipe 34 and the cold watersupply pipe 33 are connected by a connecting pipe 35 in which anautomatic cold water adjusting valve 36 is arranged. A hot water pipe 31leads from the outlet side of the mixing valve to the various faucets ofa home. The valve 36 is of the conventional type, the operation of whichis thermal controlled bythe temperature of the water passing through thepipe 34, whereby if the temperature is excessive, the valve will open toadmit cold water from the pipe 33 to mix with the hot water and moderatethe temperature of the heated water before the same passes to the pipe31.

The waterback of the boiler or furnace I is connected by insulated pipes38 to the upper portion of the inner shell 24, the said pipes 38constituting hot water inlet pipes for supplying hot water to the innercasing where said water surrounds the flue tubes 26 and copper coil 23.However, the supply of hot water from the boiler I. to the unit H isheld in check until the temperature thereof reaches a predetermined highby an aquastat 39 arranged in each pipe 38. Outlet pipes suitablyinsulated lead from the bottom of the shell 24 to the boiler I!) whilerisers 4| lead from the pipes 40 to the radiators of a domestic heatingsystem. A drain pet cock 42 is arranged in an outlet pipe 40 tofacilitate draining of the boiler water when desired.

In operation, assume that the boiler I0 is charged with boiler water asis the inner shell or casing 24 and pipes 38 and 40, while the butterflydamper valve 20 is open and the oil burner or other heat generator is inoperation. It follows, that the waste heated gases of combustion fromthe flre box of the boiler it passes through the flue pipe l8 into thegas accumulating dome l4. The by-pass flue pipe l1 being smaller indiameter than the flue pipe IS, a proportional amount of heated gasespass downwardly through,

the flue tubes 26, and through the space between the inner andouter'shells or casings i2 and 24,-

thence out through the flue I8 to the chimney ll. When the heat in thedowndraft passages reaches a predetermined temperature set by thethermal coil 23, the said coil operates to turn the rod 2| to close thebutterfly damper 20, thus diverting the entire flow of hot gases throughthe gas passages in the unit H. The aquastat 39 is set for opening at a.predetermined temperature so as to open when the boiler water in theboiler I 0 reaches a predetermined temperature. Heat from the gasespassing through the gas passages of the unit II is transferred to thewater in the inner casing or shell 24 thus boosting the temperature ofthe boiler water, while the heat of boiler water in the inner casingacts upon the copper coil 28 to heat the water 'as it passestherethrough from the cold water supply pipe 33 to the hot water supplypipe 34. As previously stated, should the temerature oi the hot waterheated by the unit H be in excess of a predetermined degree, theautomatic mixing valve 36 will operate to moderate the game by admittingcold water from the cold water supply pipe 33 into the hot water supplyline.

Should the hot gases of combustion back up in the unit H, the same willaccumulate in the dome l4 and the pressure therein will be relieved bythe blowing open of the doors l5, thus avoiding danger of explosion.

While we have shown and described what we consider to be the preferredembodiment of our invention, we wish it to be understood that suchchanges and alterations as come within the scope of the appended claimsmay be resorted to if desired.

Having thus described the invention, what we claim as new and desire tosecure by Letters Patent of the United States, is:

1. A water heating system comprising in combination, aflred boiler, awater heating unit including spaced inner and outer casings, the spacebetween said casings constituting a flue passage. vertical flue tubesextending the lqgth of the inner casing, a water coil contained withinsaid inner casing and surrounding said flue tubes, means connecting saidboiler and said inner casing for circulating boiler water through saidinner casing, a flue pipe connecting the top of said outer casing withthe flue outlet of said fired boiler for conveying hot gases ofcombustion from said boiler to the top of said outer casing for downpassage through said flue tubes and flue passage, a chimney flue leadingfrom the bottom of said outer casing for carrying off the hot gasesafter their passage through the flue tubes and flue. passage, a by-passflue pipe connecting the top of said outer casing and said chimney flue,a damper in saidby-pass flue pipe normally in an open position, andthermal actuating means responsive to the temperature of the downdraftgases passing through said chimney flue for moving said damper to closedposition when the temperature of the hot gases entering said chimneyflue reaches a predetermined degree.

2. A water heating system comprising in combination, a fired boiler, awater heating unit including spaced inner and outer casings, the spacebetween said casings constituting a flue passage,

.vertical flue tubes extending the length of the inner casing, a watercoil contained within said inner casing and surrounding said flue tubes,means connecting said boiler and said inner casing for circulatingboiler water through said inner casing, a flue pipe connecting the topof 'said outer casing with the flue outlet of said fired boiler forconveying hot gases of combustion from said boiler to the top of saidouter casing for down passage through said flue tubes and flue passage,a chimney flue leading from the bottom of said outer casing for carryingOK the hot gases after their passage through the flue tubes and fluepassage, a by-pass flue pipe connecting the top of said outer casing andsaid chimney flue, a damper in said by-pass flue pipe normally in anopen position, thermal actuating means responsive to the temperature ofthe downdraft gases passing through said chimney flues for moving saiddamper to closed position when thetemperature of the hot gases enteringsaid chimney flue reaches a predetermined degree, and automatic meansfor releasing excess pressure of the accumulation of hot gases in saidflue passage and flue tubes to the exterior of said outer casing.

3. A hot water heater comprising spaced inner and outer casings,'a domeat the top of said outer casing, hinged doors in the top of said dome, a

flue pipe leading from said dome and adapted to be connected to the flueof a fired boiler, a chimney flue pipe leading from the bottom of theouter casing, a by-pass flue pipe connecting said dome and said chimneyflue pipe, the by-pass flue pipe being of a cross sectional area less.

than that of said chimney'flue pipe, a group of flue tubes extendingthrough said inner casing, a water coil surrounding said group of fluetubes and adapted to be connectedin a water supply pipe line, hot waterinlet and outlet pipes leading from said inner casing and adapted to beconnected with the boiler waterchamber of a boiler, a normally opendamper mounted in said by-pass flue pipe, and thermal means in saidchimney flue pipe adjacent its connection with said outer casingoperatively connected to said damper for closing said damper when thetemperature in said chimney flue pipe reaches a predetermined fiegree.

ends of said innerfcasing f-a flue inlet in the topof said outer'casing,agfl'ue} outlet at the bottom of said outer casing, a hot 'water heatingcoil pipe encircling said groupof flue tubes and supported in spacedrelation with respect to said flue tubes and inner casing, and hot waterinlet and outlet pipes leading from said inner casing and adapted to beconnected with the boiler water chamber of a furnace. 4

5. A water heating unit comprising spaced inner and outer casings, thespace between said casings constituting aflue passage, a group ofvertical flue tubes extending the length of and through the ends of'theinner casing, hot water inlet means entering the top of said innercasing, hot water outlet means leading out from the lower portion ofsaid inner casing, a water coil pipe contained within said inner casingin surrounding relation with respect to said flue tubes and closelyspaced from the outermost ofsaid group of vertical flue tubes, a fluepipe connecting the top'"'of said outer casing with the flue outlet of afired boiler for conveying hot gases of combustion" bottom of said outercasing .for carrying ofl the hot gases after their passage through saidflue tubes and flue passage *JOHN WINDHEIM.

